Safety valve



Feb. 16, 1965 J. WENZL 3,169,546

SAFETY VALVE Filed Nov. 3. 1961 I @417 MM 7 [@Jw/MW/M/Em United States Patent 3,169,546 SAFETY VALVE Josef Wenzl, Klein Stockheim, near Braunschweig, Germany, assignor to Luther-Werlre, Luther & .lordan, Braunschweig, Germany Filed Nov. 3, 1961, Ser. No. 150,025 Claims priority, application Germany, Nov. 3, 196% 7 Claims. rinse-4st The present invention relates to a safety valve for preventing a container which is sensitive to pressure from being filled excessively.

It is a well-known fact that tanks of plastic, rubber, aluminum, very thin sheet steel, or similar materials are extremely sensitive to an excessive internal pressure which can be produced it" the tank is overfilled. Even though a predetermined internal pressure might be only slightly exceeded, there is considerable danger that the tank may burst and its contents will flow out. Such bursting is especially dangerous if the tank of one of the abovementioned materials is used for holding a combustible fuel or other dangerous fluid.

It is an object of the present invention to provide an automatically eiiective device for preventing such containers from being filled to such an extent that a dangerous internal pressure might be produced therein. This object is attained according to theinvention by means of a valve which is adapted to be inserted into the filling conduit leading from a source of fluid under pressure to the container. The valve member for opem'ng and closing the valve may be moved to the open position by hand arid may be held in this position by a self-engaging locking member which is released by a diaphragm which, in turn, is actuated by air which is compressed by a head of fluid if there is a danger that the container might be overfilled.

These and other features and advantages of the present invention will become more clearly apparent from the 'from a source of fluid under pressure through the valve housing 1 in the direction of the arrows, and it enters through the inlet port 2 which forms a valve chamber and it leaves through the outlet port 3. Valve housing 1 is provided with flanges 4 and 5 for connecting the feed line through which the respective fluid is supplied and the line through which the fluid after passing through the valve, is conducted to the container which is to be The inlet port 2 and th eoutlet port 3 of valvehousing 1 are separated from each other by a partition which also forms a valve seat fora valve plate 7 mounted ona slidable valve spindle 12 and forming the closure memr ber of the valve. This valve plate 7 may be lifted to the open position by handby'means of a leverS which is secured'to a pivotable shaft 9 on which a cam 16 is mounted which, when lever dis lifted (counterclockwisein FlG l), engages the lower end of valve s indle 12. When valve plate 7 is lifted to the open position,

a locking pawl 11 interengages with a locking recess 13 on the upper end of valve spindle i2. 7

Valve plate 7 is acted upon by a spring 14 which,

through a spring washen normally" biases valve plate '7 relative to the inside of housing la.

a fuel tank. The upper end of screw cap when the valve is connected to a supply of fluid under pressure and when it is not opened manually by means of lever 8 and earn it ivalve plate 7 is held in the closed position by being acted upon by the fluid pressure on its entire upper surface.

Thus, when valve plate 7 is opened manually by means of lever 55, the valve plate compresses spring 14 which is then arrested in the compressed position by insertion of locking pawl Ill into locking reces 13 on valve spindle 12, while lever 8 i then released and returns by gravity to its original position. When the detent means including pawl 11 is released from locking recess 13 on valve spindle 12, the full force of the compressed spring is also released to close the valve.

Valve spindle 12 is slidably mounted in a further partition 15 which is sealed between a pair of flanges on valve housing It and on a cylindrical housing 154 which are secured to each other. Thus, when the valve is connected at flange d to a source of fluid under pressure, for example, gasoline or another liquid fuel, this fluid will fill up the valve chamber underneath the partition 15, while the chamber above partition 15' will be merely under atmospheric pressure. For this purpose, the cylindrical housing la is provided with an air opening 1b. Locking pawl ii is pivotably mounted on a pin 16 within the cylindrical housing in and it is acted upon by a leaf spring 1'7, which may also be a torsion spring wound on pin 16, so as to bias pawl 11 at all times in the direction of locking engagement with recess 13. Pawl 11 carries a setscrew 13 which abuts the center of a diaphragm l9 bolted along its outer edge by a threaded ring or the like to the cylindrical housing Zia so as to be sealed tightly Set-screw it"; may be adjusted solas to insure the accurate operation of diaphragm 19 and pawl ii. A pressure plate 2% above diaphragm 1?, which is secured to the upper end of housing la so as likewise to be air-tight, closes a narrow gaplike chamber between this plate and diaphragm 19. This gaplike chamber communicates through a U-shaped channel 21, which extends within the wall of housing la and through a hollow screw 22 and a connecting line 23. The latter communicates with the upper end of a compression tube 24 of an oval cross section which is open at its lower end and closed at its upper end. The flanges which connect valve housirn 1 and the cylindrical housing 1a to each other are extended at the side containing the channel 21 so as to form another pair of flanges. The upper of these flanges has a threaded part into which an upright level-sensitive cylindrical tube, riser or standpipe 25 is screwed. The latter is closed at its upper end by a screw cap 25 in winch, for example, a flame filter 2'7 is inserted ii the valve is to be used on as is closed by a flap 23 which also'iorms the closure of standpipe 25. The lower end of standpipe 25 is connected to a cylindrical insert 39 which is mounted in a chamber 29 of valvehousing l and forms at its lower end a valve seat 31 with a control opening iiz' which connects the outlet '33 underneath the flame filter 27. The valve members for alternately opening and closing the; two valve seats at valveiapertures 3i and 33 are provided in the form of closure members 34 and 35 which are positively connected to each other by a rod 36.

against valve seat 6 to close the valve. in addition, 7

In the position ofthe safety valve as illustrated in FIGURE 1, closure member 35 rests on its lower valve 'seat 31 and thereby shuts ofi the pass-ageof any fluid into a) the valve outlet 3, does not exceed a predetermined permissible amount.

As soon as the danger arises that the permissible amount of fluid in the container and thus the permissible filling pressure therein might be exceeded, and as soon as the fluid head within the valve chamber indicates that a certain minimum pressure is being exceeded, closure member 35 will be lifted off its seat 31 so that the fluid will pass through the opening 32 into the tubular insert 38.

As soon as closure member 35 is lifted, the upper float 34 closes its valve seat 33. When the fluid level then rises in the tubular insert 38 until it reaches the lower end of the oval air pipe 24, the air column contained in pipe 24 will be prevented from escaping by the rising head of fluid in the tubular insert 39 so that, if the filling operation is continued and the pressure therefore increases in the fluid container, the fluid level in the tubular insert 36 also continues to rise into and Within the oval pipe 24. Consequently, an excess hydrostatic pressure is then developed in pipe 24 and in the air channel 23, 21 which is connected thereto. 'This pressure then acts within the gaplike chamber above diaphragm 19 and upon latter so as to move the diaphragm downwardly, whereby pawl 11 is disengaged from the locking recess 13 in the upper end of valve shaft 12. The compressed spring 14 thereby is released, and this spring pressure aided by the pressure of the fluid in the valve chamber as supplied by the pump will then close the valve plate 7 abruptly.

in order to permit valve plate 7 also to be released arbitrarily from its locked-open position whereby the safety valve may be manually closed in the event that this becomes necessary or desirable, a control member 37 is slidably mounted in the wall of housing In. If this control member 3'7 is depressed against the action of its spring, it will act upon an arm 11' of pawl 11 and thereby pivot the latter against the action of spring 17, whereby the pawl will be disengaged from the locking recess 13 on valve shaft 12.

If after filling one container, the'filling apparatus is to be connected to another container, it is necessary to allow the fluid which has risen above the valve member 35 again to flow out of the valve opening 32. For this purpose, a lever 38 is pivotably mounted on standpipe and adapted to act upon a projection 39 on rod 36 which connects the two closure members so that, when lever 38 is turned, rod 36 will be lifted so as to lift float 35 off its seat 33., permitting the fuel or other fluid to flow back into chamber 3 of valve housing 1. Standpipe 25 is further preferably provided with one or more inspection windows 40 at suitable levels so that an inspection may be carried out at the beginning of any filling operation to ascertain whether the standpipe has been completely drained of any fluid.

Flap 23 which closes standpipe 25 at its upper end opens automatically to permit any discharge of air or fluid, and it also forms a protective cover to prevent dust or dirt from entering and from soiling the flamepreventive filter 27. I

Although my invention has been illustrated and described with reference to the preferred embodiment thereof, I wish to have it understood that it is in no .way limited to the details of such embodiment, but is capable of numerous modifications within the scope of the appended claims.

Having thus fully disclosed claim is:

my invention, what 1 1. A safety valve comprising ahousing having an inlet opening, spring means acting upon said valve member to move the same to closed position, meansfor manually movingrsaid valve member to the openlposition, detent means adapted to engage automatically with said valve member when said valve member is moved to the open position and to arrest said valve member in said open position, a flexible diaphragm within said housing forming one wall of a closed chamber and engageable with said detent means, means for adjusting said arresting means relatively to said diaphragm, a standpipe mounted on said housing, a conduit connecting said closed chamber with the inside of said standpipe near the upper end thereof, said standpipe having a valve aperture at its lower end connecting the inside of said standpipe with said valve outlet and a passage at its upper end communicating with the atmosphere, a closure member within said standpipe normally adapted to close said valve aperture and adapted to open the same when a fluid within said valve outlet reaches a certain pressure so that fluid will then rise in said standpipe, and means for closing said passage upon opening of said valve aperture and opening said passage upon closure of said valve aperture, thereby enabling fluid rising within said standpipe to compress a gas therein which through said conduit communicates with said closed chamber so as to act upon and deflect said diaphragm and thereby act upon said detent means to disengage the same from said valve member so that said valve member will then close said valve opening under the action of said spring means.

2. A safety valve comprising a housing having an inlet and an outlet, a first partition in said housing separating said inlet and outlet and having a valve opening interconnecting said inlet and outlet, said partition forming a valve chamber communicating with said inlet, a second partition in said housing defining an air chamber having an opening toward the exterior, and having said second partition provided with an aperture connecting said two chambers, a valve member within said valve chamber for opening and closing said valve opening, said valve member having a spindle extending through said aperture into said air chamber and slidable within and guided by the wall of said aperture, spring means acting upon said valve member to move the same to a closed position wherein said valve opening is blocked, means for manually moving said valve member to an open position and for thereby compressing said spring means and moving said spindle into said air chamber, cooperating arresting means in said air chamber and on said spindle adapted to interengage automatically when said valve member is moved to the open position and to arrest said valve member in said open position, a flexible diaphragm in said housing forming one wall of said air chamber, a

narrow closed chamber along one side of said diaphragm defined by said diaphragm'and said housing at the other side of said diaphragm, a standpipe mounted on said housing and having valve apertures near its upper and lower ends, the lower valve aperture connecting the interior of said standpipe with said outlet and the upper valve aperture connecting the interior of said standpipe with the atmosphere, upper and lower closure members within said standpipe, a rod connecting said closure members with each other so that, when one of said closure members closes one of said valve apertures, the other closure member opens the other valve aperture, an air pipe mounted within said standpipe and open at its lower end facing toward said lower valve aperture while being closed at its upper end, a conduit communicating between said upper end of said air pipe and said closed chamber, said lower closure member being normally adapted to close said lower valve aperture and adapted to open the same when a fluid within said valve outlet reaches a certain pressure so that fluid will then rise in said standpipe and compressthe air within said air pipe which through said conduit communicates with said diaphragm chamber so as to act upon and deflect said diaphragm and thereby to act upon said arresting means to disengage the same from each other so that said valve member will then oneness close said valve opening by the action of said spring means. a a

3. A safety valve comprising a housing having an inlet and an outlet, a first partition in said housing as arating said inlet and outlet and having a valve opening interconnecting said inlet and outlet, said partition forming a valve chamber communicating with said inlet, a second partition in said housing defining an air chamber having an opening toward the exterior, said second partition being provided with an aperture connecting said chambers, a valve member within said valve chamber for opening and closing said valve opening,'said valve member having a spindle extending through said aperture into said air chamber and slidable within md guided by the wall of said aperture, spring means acting upon said valve member to move the same to the closed position, means for manually moving said valve member to an open position and for thereby compressing said spring means and moving said spindle into said air chamber, cooperating arresting means in said air chamber and on said spindle adapted to interengage automatically when-said valve member is moved to the open position and to arrest said valve member in said open position, means for manually disengaging said arresting means, a flexible diaphragm in said housing forming on one side thereof a wall of said air chamber, a narrowclc-sed chamber defined by said diaphragm and said housing at the other side of said diaphragm, a standpipe mounted on said housing and having valve apertures near its upper and lower ends, a flap on the upper end of said standpipe above said upper valve aperture for reventing impurities from entering the same,

said lower valve aperture connecting the interior of said standpipe with said outlet and the upper valve aperture connecting the interior of said standpipe with the atmosphere, upper and lower closure members within said standpipe, a rod connecting said closure members to each other so that, when one of said closure members closes one of said valve apertures, the other closure member opens the other valve aperture, an air pipe moanted within said standpipe and o en at its lower end facing toward said lower valve aperture while being closed at its upper end, a conduit connecting the inside of said upper end of said air pipe with said closed chamber, said lower closure member being normally adapted to close said low-er valve aperture and adapted to open the same when a fluid within said valve outlet reaches a certain pressure so that fiuid will then rise into said standpipe and compress the air within said air pipe which through said conduit communicates with said diaphragm chamber so as to act upon and deflect said diaphragm and thereby to act upon said arresting means to disengage the same so that said valve member will then close said valve opening by the action of said spring means.

4. A safety valve comprising a housing having an inlet and an outlet, a first partition in said housing separating said inlet and outlet and having a valve opening interconnecting said inlet and outlet, said partition forming a valve chamber communicating with said inlet, a second partition in said housing defining an air chamber having an opening toward the exterior and having an aperture connecting said chambers, a valve member within said valve chamber for opening and closing said valve opening said valve member having a spindle extending through said aperture into said air chamber and slidable Within and guided by the wall of said aperture, spring means actingupon said valve member to move the same to the closed position, means for manually moving said valve member to the open position and for thereby compressing said spring means and moving said spindle into said air chamber, cooperating arresting means in said air chamher and on said spindle adapted to interengage automatically when said valve member is moved to an open position and to arrest said valve member in said open position, a fiexible diaphragm in said housing forming at one side thereof a wall of said air chamber, narrow closed said housing and having valve apertures near its upper and lower ends, the lower valve aperture connecting the inside of said standpipe with said outlet and the upper valve aperture connecting the interior of said standpipe with the atmosphere, upper and lower closure members within said standpipe, a rod connecting said closure members to each other so that, when one of said closure members closes one of said valve apertures, the other closure member opens the other valve aperture, means for manually lifting said rod to open said lower valve aperture and close the upper valve aperture, an air pipe mounted Within said standpipe and being open at its lower end facing toward said lower valve aperture while being closed at its upper end, a conduit connecting the inside of said upper end of said air pipe with said closed chamber, said lower closure member being normally adapted to closeisaid lower valve aperture and adapted to open the samewhen fluid within said valve outlet,

reaches a certain pressure so that fluid will then rise into said standpipe and compress the air within said air pi e which through said conduit communicates with said diaphragm chamber so as to act upon and deflect said diaphragm and thereby to act upon said arresting means to disengage the same so that said valve member will then close said valve opening by the action of said spring means.

5. A safety valve comprising a housing having an inlot and an outlet, a first partition in said housing separating said inlet and outlet and having a valve opening connecting said inlet and outlet, said first partition forming a valve chamber communicating with said inlet, a second partition in said valve housing defining an air chamber having an opening toward the exterior, said second partition being provided with an aperture connecting said chambers, a valve member within said valve chamber for opening and closing said valve opening, said valve member having a spindle extending through said aperture into said air chamber andslidable Within and guided by the I wall of said aperture, spring means acting upon said valve member to move the same to the closed position, means operable from the outside of said housing for manually moving said valve member to the open position and for thereby compressing said spring means and moving said spindle into said air chamber, said spindle having a recess near its upper end, a pawl-like member pivotably mounted in said air chamber, a spring member acting upon said pawl-like member so that, when said valve member is moved to said open position, said pawl-like member will snap automatically into engagement with said recess to arrest said valve member, means operablefrom the outside of said housing for manually disengaging said pawl-like member from said recess, a flexible diaphragm in said housing forming at one side thereof'a wall of said air chamber, means for adjusting said pawlsame, the lower valve aperture connecting the interionof said standpipe with said outlet and the upper valve aperture connecting the interior of said standpipe with the atmosphere, upper and lower closure members within said standpipe, a rod extending'through said standpipe and connecting said closure members to eachother so that,

when one of said closure members closes one of said valve apertures, the other closure member opens the other valve aperture, means operable from the outside of said housing for manually lifting said rod to open said lower valve aperture and to close said upper valve aperture, an

air pipe mounted Within said standpipe and being open I i at its lower end facing toward said lower valve aperture while being closed at its upper end, a conduit connecting the interior of said upper end of said 'air pipe with said closed chamber, said lower closure member being normally adapted to close said lower valve aperture and adapted to open the same when a fluid within said valve outlet reaches a certain pressure so that fluid will then rise into said standpipe and compress the air within said air pipe which through said conduit communicates with said diaphragm chamber so as to act upon and deflect said diaphragm and thereby to act upon said pawl-like member to disengage the same from said recess so that said valve member will then close said valve opening by the action of said spring means.

6. A safety valve responsive to rise of a liquid level, comprising a housing having an inlet and an outlet; a partition in said housing defining therein a first compartment communicating with said inlet and a second compartment communicating with said outlet, said partition being provided with a valve opening interconencting said first and second compartments; a valve member displaceable relative to said partition between a first position wherein it blocks said opening and a second position wherein it is spaced therefrom to permit passage of a liquid between said chambers; biasing means bearing upon said member to urge it into said first position; detent means in said housing for releasably arresting said valve member in said second position; manually operable means for shifting said valve member against the force of said biasing means from said first position into said second position for engagement by said detent means; a deflectable diaphragm forming within said housing a compression chamber and engageable with said detent means for releasing said valve member; an upright level-sensitive riser communicating at its lower end with said second compartment and at its upper end with the atmosphere; means in said riser for closing said upper end upon a rise in fluid pressure in said second compartment whereby air within said riser is compressed; and a downwardly open compression tube disposed within said riser with its mouth above the lower end thereof, said tube communicating with said pressure chamber whereby a rise in liquid level to block the mouth of said tube will effect an 8 increase in the pressure within said chamber to deflect said diaphragm and release said detent means.

7. A safety valve responsive to rise of a liquid level, comprising a housinug having an inlet and an outlet; a partition in said housing defining therein a first compartment communicating with said inlet and a second compartment communicating with said outlet, said partition being provided with a valve opening interconnecting said first and second compartments, a valve member displaceable relative to said partition between a first position wherein it blocks said opening and a second posit-ion wherein it is spaced therefrom to permit passage of a liquid between said chambers; biasing means bearing upon said member to urge it into said first position; detent means in said housing for releasably arresting said valve member in said second position; manually operable means for shifting said valve member against the force of said biasing means from said first position into said second position for engagement by said detent means; a defiectable diaphragm forming within said housing a compression chamber and engageable with said detent means for releasing said valve member; an upright level-sensitive riser communicating at its lower end with said second compartment; closure means at said lower end of said riser for temporarily blocking the influx of liquid from said second compartment until a predetermined pressure level at said outlet resulting from a rise in liquid level adjacent said outlet is attained; and a downwardly open compression tube disposed within said riser with its mouth above the lower end thereof, said tube communicating with said pressure chamber whereby a rise in liquid level to block the mouth of said tube will effect an increase in the pressure within said chamber to deflect said diaphragm and release said detent means.

References Cited by the Examiner UNITED STATES PATENTS ISADOR \VEIL, Primary Examiner. 

1. A SAFETY VALVE COMPRISING A HOUSING HAVING AN INLET AND AN OUTLET, A PARTITION IN SAID HOUSING SEPARATING SAID INLET AND OUTLET AND HAVING A VALVE OPENING INTERCONNECTING SAID INLET AND OUTLET, A VALVE MEMBER SLIDABLY MOUNTED WITHIN SAID HOUSING FOR OPENING AND CLOSING SAID VALVE OPENING, SPRING MEANS ACTING UPON SAID VALVE MEMBER TO MOVE THE SAME TO THE CLOSED POSITION, MEANS FOR MANUALLY MOVING SAID VALVE MEMBER TO THE OPEN POSITION, DETENT MEANS ADAPTED TO ENGAGE AUTOMATICALLY WITH SAID VALVE MEMBER WHEN SAID VALVE MEMBER IS MOVED TO THE OPEN POSITION AND TO ARREST SAID VALVE MEMBER IN SAID OPEN POSITION, A FLEXIBLE DIAPHRAGM WITHIN SAID HOUSING FORMING ONE WALL OF A CLOSED CHAMBER AND ENGAGEABLE WITH SAID DETENT MEANS, MEANS FOR ADJUSTING SAID ARRESTING MEANS RELATIVELY TO SAID DIAPHRAGM, A STANDPIPE MOUNTED ON SAID HOUSING, A CONDUIT CONNECTING SAID CLOSED CHAMBER WITH THE INSIDE OF SAID STANDPIPE NEAR THE UPPER END THEREOF, SAID STANDPIPE HAVING A VALVE APERTURE AT ITS LOWER END CONNECTING THE INSIDE OF SAID STANDPIPE WITH SAID VALVE OUTLET AND A PASSAGE AT ITS UPPER END COMMU- 